The concept of dry transfer impact printing with a print wheel is known in the art as in, for example, U.S. Pat. No. 4,074,798 issued to Burger. Its application to the printing of characters on a tape is shown in U.S. Pat. No. 3,834,507 issued to Bradshaw. A system similar to Bradshaw, but automated, is shown in PCT Publication No. WO/8203600. The system shown in Burger is effective for characters having a relative small pitch and point, such as used in typewriters. When used to create letters of varying sizes, for example, up to 36 point, simple rotation and shifting of the print wheel is insufficient to move characters of such size into alignment with the print head. In the prior art such as Bradshaw and the PCT Publication, this problem has been circumvented by merely providing a single circumferential track having letters thereon for impact printing. This system, however, becomes extremely cumbersome as the number and size of letters increases, since the print disk must be of increasing diameter, and time required to print succeeding characters thereby increases substantially.
The present invention overcomes these problems in the prior art relating to speed and size limitations, while providing an economical and simple to manufacture system for positioning the appropriate character in place for impact printing.